Band-like cloth twist detecting device and twist eliminating machine

Abstract

A twist detecting device is capable of detecting twist of band-like cloth even though the thickness of the band-like cloth is changed, and a twist eliminating machine incorporates the twist detecting device. The twist detecting device is constructed so that cloth contactors 3a, 3b are supported by a pair of supporting axes 2a, 2b, the arcuate contacting portion r of these cloth contactors is brought into contact with band-like cloth w1 or w2, the respective cloth contactors 3a, 3b are caused to rock and to be displaced around their supporting axes by engagement with wrinkle lines of the band-like cloth, and the rocking and displacement are detected as twist information, wherein a cloth intermediate contacting member which is able to detect to the twist of band-like cloth is rockably provided around an intermediate supporting axis 13 juxtaposed between pair of supporting axes deep in a triangle-shaped space formed at the opposed sides of the arcuate contacting member of pair of cloth contactor, so that the cloth intermediate contacting member 12 is caused to rock and to be displaced around the intermediate supporting axes by engagement with the cloth contactors, and the rocking and displacement are detected as twist information of the band-like cloth.

What is claimed is: 
     
       1. A twist detecting device for detecting twists in a moving band of cloth turned in around its axis of movement by engaging wrinkle lines in the cloth comprising: a pair of juxtaposed supporting axes;   a cloth contactor supported at each of the supporting axes, each cloth contactor having an arcuate contacting portion for contacting the moving band of cloth, said arcuate contacting portions extending toward one another to define a nip;   a spring biasing each of the cloth contactors in a first circumferential direction around its supporting axis to an initial position;   a cloth intermediate contacting member rockably supported about a supporting axis and positioned between said arcuate contacting portions of said cloth contactor, adjacent to said nip, said cloth contactors and said cloth intermediate contacting member pivoting around their supporting axes in response to engaging wrinkle lines in the moving band of cloth; and   an arrangement for outputting the pivoting of said cloth contactors and said cloth intermediate contacting member about their axes as information about twists in the moving band of cloth.   
     
     
       2. A twist detecting device according to claim 1, wherein said cloth contactors and said cloth intermediate contacting member each have a pivotal connection with a common displaceable linkage member, said cloth intermediate contacting member has a contacting portion for contacting the moving band of cloth, each cloth contactor defines a first lever arm between its arcuate contacting portion and its supporting axis and a second lever arm between its supporting axis and its pivotal connection with the common displaceable linkage member, and said cloth intermediate contacting member defines a first lever arm between its contacting portion and its supporting axis and a second lever arm between its supporting axis and its pivotal connection with the common displaceable linkage member, wherein the ratio of the first to the second lever arms of the intermediate contacting member is different from the ratio of the first to the second lever arms of the cloth contactors, whereby the intermediate contacting member is pivoted about its axis with less force than a force required to pivot the intermediate contacting members around their axes. 
     
     
       3. A twist detecting device as set forth in claim 1, wherein an arcuate recess is defined in the arcuate contacting portion of each of said cloth contactors, and said cloth intermediate contacting member extends into said recesses. 
     
     
       4. A twist eliminating machine for eliminating twists in a moving band of cloth turned in around its axis of movement comprising: a cloth guide arrangement for guiding the moving band of cloth in a first direction in a first run of the band and in a second direction in a second run of the band;   a pair of juxtaposed supporting axes;   a cloth contactor supported at each of the supporting axes, each cloth contactor having an arcuate contacting portion for contacting the moving band of cloth, said arcuate contacting portions extending toward one another to define a nip;   a spring biasing each of the cloth contactors in a first circumferential direction around its supporting axis to an initial position;   a cloth intermediate contacting member rockably supported about a supporting axis and positioned between said arcuate contacting portions of said cloth contactor, adjacent to said nip, said cloth contactors and said cloth intermediate contacting member pivoting around their supporting axes in response to engaging wrinkle lines in the moving band of cloth;   an arrangement for outputting the pivoting of said cloth contactors and said cloth intermediate contacting member about their axes as information about twists in the moving band of cloth; and   a cloth turning arrangement for turning the band in the first run in a direction around axis of movement of the band in response to twist detected by the twist detecting device.   
     
     
       5. A twist eliminating machine as set forth in claim 4, further comprising: a detection time judging means for judging the time during which the twist is continuously detected by the twist detecting device; and   means for operating said cloth turning device to intermittently turn the band in an appointed direction around the axis of movement of the band for a time period whose duration is dependent on the length of the time during which the twist is continuously detected by the twist detecting device.   
     
     
       6. A twist detecting device for detecting twists in a moving band of cloth turned in around its axis of movement by engaging wrinkle lines in the cloth comprising: a pair of juxtaposed supporting axes;   a cloth contactor supported at each of the supporting axes, each cloth contactor having an arcuate contacting portion for contacting the moving band of cloth, said arcuate contacting portions extending toward one another to define a nip;   a spring biasing each of the cloth contactors in a first circumferential direction around its supporting axis to an initial position;   a cloth intermediate contacting member rockably supported about a supporting axis and positioned between said arcuate contacting portions of said cloth contactor, adjacent to said nip, said cloth contactors and said cloth intermediate contacting member pivoting around their supporting axes in response to engaging wrinkle lines in the moving band of cloth; and   means for outputting the pivoting of said cloth contactors and said cloth intermediate contacting member about their axes as information about twists in the moving band of cloth.   
     
     
       7. A twist detecting device according to claim 6, wherein said cloth contactors and said cloth intermediate contacting member each have a pivotal connection with a common displaceable linkage member, said cloth intermediate contacting member has a contacting portion for contacting the moving band of cloth, each cloth contactor defines a first lever arm between its arcuate contacting portion and its supporting axis and a second lever arm between its supporting axis and its pivotal connection with the common displaceable linkage member, and said cloth intermediate contacting member defines a first lever arm between its contacting portion and its supporting axis and a second lever arm between its supporting axis and its pivotal connection with the common displaceable linkage member, wherein the ratio of the first to the second lever arms of the intermediate contacting member is different from the ratio of the first to the second lever arms of the cloth contactors, whereby the intermediate contacting member is pivoted about its axis with less force than a force required to pivot the intermediate contacting members around their axes. 
     
     
       8. A twist detecting device as set forth in claim 6, wherein an arcuate recess is defined in the arcuate contacting portion of each of said cloth contactors, and said cloth intermediate contacting member extends into said recesses. 
     
     
       9. A twist eliminating machine for eliminating twists in a moving band of cloth turned in around its axis of movement comprising: cloth guide means for guiding the moving band of cloth in a first direction in a first run of the band and in a second direction in a second run of the band;   a pair of juxtaposed supporting axes;   a cloth contactor supported at each of the supporting axes, each cloth contactor having an arcuate contacting portion for contacting the moving band of cloth, said arcuate contacting portions extending toward one another to define a nip;   a spring biasing each of the cloth contactors in a first circumferential direction around its supporting axis to an initial position;   a cloth intermediate contacting member rockably supported about a supporting axis and positioned between said arcuate contacting portions of said cloth contactor, adjacent to said nip, said cloth contactors and said cloth intermediate contacting member pivoting around their supporting axes in response to engaging wrinkle lines in the moving band of cloth;   means for outputting the pivoting of said cloth contactors and said cloth intermediate contacting member about their axes as information about twists in the moving band of cloth; and   cloth turning means for turning the band in the first run in a direction around the axis of movement of the band in response to twist detected by the twist detecting device.   
     
     
       10. A twist eliminating device as set forth in claim 9, further comprising: a detection time judging means for judging the time during which the twist is continuously detected by the twist detecting device; and   means for operating said cloth turning device to intermittently turn the band in an appointed direction around the axis of movement of the band for a time period whose duration is dependent on the length of the time during which the twist is continuously detected by the twist detecting device.